[0001] The present invention concerns improvements in and relating to a hermetically sealed
infection control bedding product such as a pillow, duvet, mattress, cushion and such
like. The present invention also relates to a method of manufacture of a vented hermetically
sealed infection control bedding product.
Background to the invention
[0002] Infection control and cross infection present a major problem for hospitals today,
leading to considerable expense and inconvenience. Bacterial strains have developed
which are increasingly more resistant to treatment by antibiotics. Therefore, once
an infection is established in a hospital, it is often difficult to eradicate and
can spread quite rapidly. A problem known as "strikethrough", where a contaminated
fluid penetrates to an interior of a infection control bedding product such as a pillow,
duvet, mattress, or cushion, is well known. If "strikethrough" occurs, then there
is a considerable risk of cross infection associated with any of these infection control
bedding products since they are likely to be used subsequently by many different patients.
Indeed, this problem arises in any situation where there is a regular change in persons
using pillows, duvets and the like, such as, for example, in hotels and guesthouses.
Furthermore, in the home, many people with allergies and breathing disorders have
problems with fungal infection and dust mites.
[0003] There are numerous commercially available materials typically used for waterproof
covers on mattresses, typically comprising a knitted or woven nylon fabric, with a
thermoplastic coating, typically polyurethane, applied. The knitted or woven fabric
provides mechanical strength, while the thermoplastic (polyurethane) coating provides
waterproofing.
[0004] Some such fabrics are termed "vapour permeable" because tiny pores exist at sub-micron
level in the coating, that nominally allow transport of water vapour molecules. However,
these fabrics do not allow transfer of air at sufficient rates to ventilate a pillow.
[0005] United States Patent Specification No.
US 4 637 377 discloses a surgical pillow for supporting the heart or other body organs of a patient
during surgical procedures. The surgical pillow disclosed in
US 4 637 377 has a foam filled casing with a vent in the casing to permit release of entrapped
air within the casing upon compression of the pillow during use.
[0006] United States Patent Specification No.
US 5 038 431 discloses a pillow for dispensing medication. The pillow has an outer sheet forming
a pocket for reception of filling material. The pocket has a vent opening and the
filling material is impregnated with a medicament. When the vent is open, a person
is exposed to medicament vapour which escapes through the vent opening.
[0007] These prior art pillows do not address the problem of "strikethrough".
[0008] U.S. Patent Specification No. 4 445 241 discloses an air tight and fluid tight cover for padded bodies, mattresses and the
like. The cover has a top, a bottom and a plurality of side parts. At least one opening
provides ventilation between the interior of the cover and the ambient atmosphere.
At least two of the side parts are formed by at least an interior, middle and exterior
layer of material. Air passage openings offset with respect to each other are provided
in the interior and middle layers of material. At least one filter is disposed between
the middle and outer layer of material. A plurality of connecting seams extend partially
transversely across the width of the side part from diametrically opposite points
of the upper and lower longitudinal edges of the side parts toward a longitudinal
center line bisecting the side part. The connecting seams define a plurality of pockets
in which the filters are disposed. The connecting seams also define air passages between
the individual layers of material for trapping coarse granular particles therein.
[0009] US-A-4,445,241 discloses a moisture and air-tight cover for a pillow in which welded seams are provided
to constitute pockets for reception of filters for particles and bacteria. This is
a complex product which is difficult and expensive to produce. The seams define a
serpentine air passage between the interior and exterior of the pillow and each air
stream contains at least two filters. However, these filters are not, and cannot be,
physically connected to one another by welding or otherwise, as in the present invention,
and in fact at least one filter at the outer opening of the air passage can be removed
through slit-shaped openings 28 (see column 4, lines 13 to 15). The serpentine passage
actually provides a breeding ground for bacteria thus defeating the purpose.
[0010] A further distinction and advantage of the present invention as compared to
US-A-4,445,241 is that the filter cannot be removed from the pillow deliberately or inadvertently,
thereby possibly compromising the filtration, as is possible with the design of
US-A-4,445,241.
[0011] A major problem to overcome when developing a sealed pillow is to ensure adequate
ventilation of the pillow core. A pillow may be made airtight by using an occlusive
medium for the cover, and welding the seams. However, the lack of ventilation in such
a pillow creates problems in use, such as the following problems:
- 1) When the head rests on the pillow, the pillow does not deflate. This is uncomfortable,
and creates an unstable surface for the head to rest on.
- 2) Impact to the pillow, either accidentally or when the head first makes contact,
creates a great deal of stress on the seams, which may burst as a result.
- 3) Gradual ingress of water vapour particles by diffusion creates condensation within
the pillow, leading to accelerated degradation of the materials within.
[0012] Furthermore, many attempts have been made to provide pillows, cushions or mattresses
that have a barrier for contaminant particles or liquid, but none has been entirely
successful. The best effort to date and currently in use in the healthcare sector,
is the pillow disclosed in the Applicants'
patent specification no. EP 1 222 886. Nevertheless, the infection control bedding product of the present invention provides
significant advantages over the pillow disclosed in
EP 1 222 886.
[0013] European Patent Specification No.
EP 1 222 886 discloses a pillow comprising a sealed outer liquid impermeable cover, filling material
retained within the outer cover, a vent in the cover communicating between an interior
and an exterior of the cover and a bacteriological air filter means mounted across
the vent to provide for filtering of air passing through the vent, wherein the filter
comprises an outer layer of liquid-resistant material with a number of superimposed
inner filter material layers attached to the outer layer, and wherein the material
layers are welded together and to the cover across the vent. Provision of a bacteriological
filter prevents the ingress of bacteria to an interior of the cover.
[0014] The outer layer of the filter of the pillow disclosed in
EP 1 222 886 does not provide adequate liquid resistance. Even if a filter medium constructed
using the same materials as the outer layer of the
EP 1 222 886 filter could be made to be fully liquid resistant, such a filter medium would not
provide adequate ventilation for the product to breathe, resulting in ballooning of
the pillow in use. This would provide an uncomfortable surface for a user to rest
on, and could burst from internal pressure when in use. In addition, the method of
welding each of the five layers of the filter of
EP 1 222 886 is time consuming and inhibits the viability of the product from a mass production
and commercial point of view.
[0015] For example,
EP 1 222 886 only teaches a liquid resistant as opposed to a liquid proof outer layer to the filter.
The textile disclosed in
EP 1 222 886 is a nylon material which will admit liquid at relatively low levels of pressure
(i.e. relative to the membrane of the present invention). If the textile disclosed
in
EP 1 222 886 was made liquid proof, it would require that the pore size would be reduced to such
an extent that such pore size would prevent the pillow from "breathing" or deforming,
or inhaling/exhaling to the required level.
[0016] The present invention addresses and solves these technical problems. As will be further
described in detail hereinbelow, the filter membrane included in the present invention
is more like a strengthened skin that breathes through osmosis. This is in contrast
to the filter of
EP 1 222 886 which must be more coarse in order to form part of the product and is only liquid
resistant rather than liquid proof. The pillow of
EP 1 222 886 has a woven synthetic outer textile backed by non-woven polyester layers. The membrane
of the present invention is fundamentally different from the medium disclosed in
EP 1 222 886.
[0017] The filter membrane in accordance with the present invention overcomes a number of
technical problems. The filter membrane included in the present invention, being like
a thin skin, must be strengthened so that the infection control product of the present
invention would be fit for use in the environment in which it would be used and so
that it could withstand the challenges that are likely to be present in use. This
needed to be achieved without compromising key properties of the filter medium and
the pillow including filtration of contaminants and "breathability" of the pillow.
[0018] EP 1 222 886 discloses the welding together of five or six layers of material. If, as is taught
in
EP 1 222 886, each layer is welded to the other and then to the liquid resistant outer fabric
and then the whole medium is welded across the aperture in the pillow, then the process
becomes non-viable from a manufacturing and mass production point of view. If they
are all welded together in one action, then the seal integrity and consequently, the
pillow is compromised as the strength and integrity of the seal between each individual
layer is compromised. Further, the drawings and description of
EP 1 222 886 illustrate that the filter medium should run diagonally and be welded at one end
into the top seam of the pillow and at the other end into the side seam of the pillow.
This means that a further thick 2 thick layer of PU-coated fabric need to be welded
through, in addition to the 5/6 layers of the medium, thereby giving rise to further
manufacturing challenges and quality/integrity issues. In other words,
EP 1 222 886 does not teach a product that when mass-produced can provide the benefits of the
present invention.
[0019] A further problem that emerged with the pillow disclosed in
EP 1 222 886 was that the filter medium itself as well as the seal between the filter medium and
the pillow cover could burst or tear if pressure equivalent to a patient leaning on
their elbow, was applied directly on the filter medium itself. Therefore, a further
problem overcome by the present invention is the provision of a new and vastly improved
filter medium that could withstand pressure of this nature whilst providing efficient
bacteriological properties.
[0020] The filter medium disclosed in
EP 1 222 886 is described as efficient to block the passage of particles having a size of 0.6
microns or greater whereas the present invention including a new medical membrane
design which has been proven to be efficient to block the passage of particles having
a size of 0.2 microns or greater. Therefore the present invention addresses a greater
number and wider category of possible contaminants.
[0021] Accordingly, the present invention relates to an improved infection control bedding
product, e.g. a pillow, having technical improvements in particular, superior liquid
resistance over the pillow disclosed in
EP 1 222 886.
Summary of the invention
[0022] According to the present invention, there is provided a hermetically sealed infection
control bedding product such as a pillow, duvet, mattress, cushion or such like having
a sealed cover and having a resiliently deformable filling material, comprising: a
vent means in the cover, characterised in that the vent means comprises a filter medium
including a filter membrane for the removal of particles of microbial size and wherein
the filter medium also comprises a strengthening layer of material for providing mechanical
strength to the filter medium, whereby the filter medium allows air flow therethrough
but is substantially impermeable to liquid while maintaining a barrier to particles
of microbial size.
[0023] Thus the infection control product of the present invention has the advantage that
the vent allows air to pass through so as to provide ventilation for the pillow while
preventing liquid including water moisture, water droplets, human sweat, sputum, urine
from passing through the vent.
[0024] Accordingly, the problems associated with the prior art are overcome by incorporating
into the cover of the pillow, a vent comprising a filter medium which allows substantial
air flow, but is substantially impermeable to liquid and maintains a barrier to particles
of microbial size.
[0025] Conveniently, an aperture is formed in the cover of the product and is adapted to
receive the vent.
[0026] Ideally, the aperture in the cover of the infection control product is located so
that the seam of the filter medium and aperture is not integral with any perimeter
seam of the cover of the infection control product.
[0027] Preferably, the layer of strengthening material comprises a material providing mechanical
strength, and advantageously may comprise a spun non-woven synthetic material such
as polypropylene (PP).
[0028] Preferably, the filter medium includes a means for substantially preventing fluid
ingress, while allowing air to permeate. Conveniently, the liquid resistance may be
achieved by virtue of the filter membrane being manufactured of a hydrophobic material
or oleophobic material.
[0029] Advantageously, the filter membrane comprises a thermoplastic non-woven material
which may include polytetraflouroethylene (PTFE).
[0030] In the preferred embodiment, the filter membrane is manufactured of an oleophobic
expanded polytetrafluoroethylene (PTFE) material. Ideally, the filter membrane is
manufactured of an oleophobic PTFE membrane and also includes a non-woven polyvinyl
chloride (PVC) membrane support.
[0031] The filter membrane functions as a bacteriological filter. This has the advantage
that it prevents the ingress of bacteria to an interior of the cover.
[0032] Advantageously, the filter membrane is adapted to block passage of particles having
a size of 0.2 microns or greater.
[0033] Preferably, the pore size of the filter membrane is between 0.2 microns and 4 microns,
and is preferably between 0.5 microns and 4 microns, and may be between 1 and 4 microns.
Advantageously, the pore size of the filter membrane may be a size between 2 and 4
microns.
[0034] Given the low micron size of the pore size of the filter membrane, there is a risk
that if the filter medium of the present invention was incorporated in a pillow in
the same way as described in
EP 1 222 886 that the internal pressure when a patient exerts a force onto the pillow would cause
the pillow to tear. It should be noted that the same risk applies to the majority
of the uses to which the filter medium is suited e.g. wheelchair cushion, mattress
and so on.
[0035] Accordingly, in the preferred embodiment, the filter medium comprising the filter
membrane and strengthening material are bonded together and to the cover of the infection
control product, at an aperture in the cover of the infection control bedding product
such as a cushion, pillow, duvet, mattress or such like so as to provide a vent in
the infection control bedding product. The bonding of the layers together is preferably
achieved by welding. In the most preferred embodiment, the vent includes a gasket
(PU) and the gasket is also bonded with the filter medium to the cover of the infection
control product so as to achieve a sealed vent.
[0036] Advantageously, the cover of the infection control bedding product such as a pillow
is manufactured of polyurethane coated polymeric material, for example polyurethane
coated nylon.
[0037] Most preferably, the infection control product of the present invention includes
a gasket which is ideally of dimensions corresponding to the dimensions of the aperture
in the cover of the infection control product into which the vent will be located
and subsequently bonded to the cover of the infection control product.
[0038] Conveniently, the gasket is manufactured of the same material as the cover of the
infection control product. Advantageously, the gasket is manufactured of a thermoplastics
material such as polyurethane (PU). The inclusion of the gasket in the vent of the
infection control product ensures that the edges of the assembled vent comprising
the filter membrane/strengthening layer and gasket bonded to the cover fabric of the
bedding product (such as a pillow cover) are sealed and impermeable to liquid.
[0039] After the components of the vent have been located in the aperture in the cover of
the product, all of the components of the vent together with the cover of the infection
control product itself are bonded together in a manner that provides a seal which
is impermeable to liquid.
[0040] The present invention also provides a method of manufacture of the hermetically sealed
infection bedding product comprising the steps of
- a) providing a filter membrane
- b) providing a strengthening layer
- c) providing a cover of the bedding product, the cover having an aperture adapted
to receive the filter membrane and strengthening layer; and
- d) affixing the layers a), b) and c) together so that the layers are affixed together
to form a seal which is impermeable to liquid.
[0041] Ideally, between steps (b) and (c), a gasket is provided and the gasket is also affixed
with the filter membrane and the strengthening layer to the cover of the product.
[0042] Conveniently, the step of affixing the layers together may be achieved by bonding
such as by glueing or welding as the layers must be affixed together so as to form
a seal which is impermeable to liquid.
Detailed Description of the Invention
[0043] The invention will now be described more particularly with reference to the accompanying
drawings, in which are shown, by way of example only, two embodiments of a pillow
in accordance with the present invention.
[0044] The embodiments shown in the drawings comprise an infection control pillow but of
course, it is to be understood that many other infection control bedding products
could be manufactured in accordance with the present invention.
[0045] In the drawings:
Figure 1 is a perspective view of the outside of a first embodiment of a pillow in
accordance with the invention;
Figure 2 is a perspective view of the outside of a pillow in a second embodiment;
Figure 3 is a plan view of the inside of a pillow in the second embodiment;
Figure 4 is an exploded view of the layers of materials included in a third and most
preferred embodiment of the infection control bedding product of the present invention;
Figure 5 is a close up of the exploded view of the infection control bedding product
in the third embodiment, shown in Figure 4;
Figure 6 is a perspective view of the third embodiment of the infection control bedding
product of Figures 4 and 5, with the layers now shown assembled on the infection control
pillow product;
Figure 7 is an exploded cross sectional view of the assembled layers including the
pillow cover, PU gasket, spun-bonded polypropylene strengthening layer and the medical
membrane stacked on top of each other, in situ, before welding. (After welding, the layers will be compressed together);
Figure 8 is a perspective view showing the assembled layers stacked on top of the
welding tool with the welding tool surface being dimensioned so that it has a greater
surface area than the area of the assembled layers so as to ensure that the respective
edges are completely sealed together; and
Figure 9 is a plan view showing the final infection control product with the pillow
cover welded to the filter medium and the strengthening layer.
[0046] Referring now to Figure 1, a first embodiment of a pillow in accordance with the
invention is indicated generally by reference numeral 10. The pillow 10 comprises
a waterproof coated fabric cover 1 and incorporates a section of filter medium 2.
The pillow is, preferably, ultrasonically welded at seams 3. The fabric cover 1 encases
the filling of the pillow and is formed of a weldable material which is coated in
polyurethane which provides a fluid resistant (waterproof) coating on the cover.
[0047] The filter medium comprises a filter membrane which may comprise a non-woven membrane,
made of thermoplastic material. In the preferred embodiment, the filter membrane is
manufactured of an oleophobic expanded PTFE membrane having a membrane support backing
comprised of a non-woven polyvinyl chloride (PVC). The PVC backing layer is fused
or laminated to the PTFE filter membrane. It has been found by experimentation that
the optimal pore size of the filter membrane for this use is in the range of 2 - 4
microns. This pore size allows sufficient air-flow to ventilate the pillow dynamically
when impacted by a user's head. Air flow through the pillow of the invention, has
been measured and found to be in the region of 20 - 40 Litres per minute per square
centimeter at 1 bar differential pressure. This pore size has also proved by experimentation
to have 100% filtration efficiency in terms of removing microbial load, while providing
resistance to water in the region of 0.2-0.8 bar entry pressure.
[0048] The intrinsic mechanical weakness of the necessarily thin PTFE/PVC filter membrane
is overcome by providing an additional strengthening layer of a synthetic material
such as polypropylene, preferably spun fibre polypropylene, which provides mechanical
strength to the filter membrane. This assembly is referred to as the "filter medium",
indicated generally by reference numeral 2 in figure 1.
[0049] Referring now to Figures 2 and 3, a preferred arrangement for welding the various
components together will be described. In the drawings, like numerals refer to like
features of the pillow in the first and second embodiments.
[0050] In the first embodiment of the pillow 10, the filter medium 2 spans the entire corner
of the pillow 10 and so the filter medium 2 is incorporated into the welded seam.
However, it was found by experimentation that if a pillow bursts in use, the most
common point of failure was the welding seam, at that point where the filter medium
2 is incorporated into the seam. This mechanical failure was thought to be happening
for two reasons:
- 1) The geometry of the seams renders them subject to peel forces; and
- 2) The weld strength when welding the filter medium 2 to another substrate is substantially
stronger when the expanded polytetrafluoroethylene (PTFE) (strength-providing) layer
is next to the substrate to which the material is being welded. On the other hand,
if the waterproof layer (i.e. non-woven PVC) is next to the substrate to which the
filter medium is being welded, delamination of this waterproof layer may occur, and
a strong weld is not achieved.
[0051] The geometry of the first embodiment of the pillow 10 in which the filter medium
is incorporated into the seam dictates that, for the waterproof PVC layer to be facing
outwards which is necessary to avoid wetting of the expanded polytetrafluoroethylene
(PTFE) layer), the waterproof PVC layer had to comprise the welded face of the filter
medium. This arrangement gave rise to a weaker weld than was desired.
[0052] Accordingly, a second embodiment is provided and a pillow in this second embodiment
of the invention is shown in Figures 2 and 3. The pillow in this second, preferred
embodiment, is indicated generally by reference numeral 20 and comprises a waterproof
pillow cover 21, a filter medium 22, and seam 23. The cover 21 is manufactured of
polyurethane-coated nylon. Referring to figure 3, in the second embodiment, the pillow
20 includes a window 24 which is die-cut in the cover material 21. This window 24
may be any shape, and is substantially removed from the seams 23 of the pillow. Figure
3 shows the inside of the pillow cover 21.
[0053] As shown in Figure 3, the filter medium 22 is cut so that it is a similar shape and
of similar dimensions to those of the window (aperture) 24 except that the filter
medium 22 is slightly larger than the window 24 to allow overlap of the filter medium
22 beyond the edges of the window 24. The orientation of the filter medium 22 is such
that the filter membrane/waterproof layer is facing outwards (away from the viewer
in this figure) and the support layer which provides mechanical strength, forms the
facing layer for welding to the coated side of the pillow cover.
[0054] This arrangement solves both of the mechanical failure problems by removing the filter
medium 22 from the seam area, to an area where no peel forces are experienced, and
by maintaining the correct orientation of surface contact between media for welding.
[0055] With the filter medium of the present invention, the filter membrane provides the
liquid resistance, but allows for air permeability due to the construction of the
PVC backing. The addition behind the filter membrane of the strengthening layer, preferably
manufactured of a spun non-woven polypropylene (PP) material (alternatively, other
synthetic materials could be used for this purpose), provides the additional strength
required around the welded join of the filter medium to the window/strip provided
in the pillow cover for the application of the filter. This is achieved because of
the strengthening layer being formed of meltable material (i.e. the non-woven PP)
being melted into the PU coating of the pillow cover fabric as well as into the filter
membrane, thereby providing a stronger welded seam to prevent the risk of the infection
control product bursting.
[0056] In addition, the window/strip is designed so that the seams (joining edges) of the
filter medium/window are not integrated with the main perimeter welded seam of the
pillow where it would weaken the overall strength of the seam. Therefore, the window
has been re-designed in such away that its edges or "frame" is separate and distinct
from the edges of the pillow cover allowing for the strong weld of the medium/window
described whilst maintaining the integrity of the main welded seam of the pillow.
[0057] In the second embodiment which is shown in and described with reference to Figures
2 and 3, only one vent is provided on the pillow 20. However, it will be understood
that any number of vents may be provided as required, each with an appropriate bacteriological
filter medium associated therewith.
[0058] Referring now to Figures 4, 5, 6 and 7, a third embodiment of the infection control
bedding product will now be described. In the drawings of the product in the third
embodiment, like numerals refer to like features shown of the first and second embodiment.
[0059] Referring initially to the Figures 4, 5, 6 and 7, the infection control pillow in
the third embodiment is indicated generally by reference numeral 30 and the pillow
30 includes a vent indicated generally by the reference numeral 32. The infection
control pillow 30 includes a pillow cover 31, a vent 32 comprising a polyurethane
(PU) gasket 36, spun-bonded polypropylene strengthening layer 35 and filter membrane
(also referred to hereinbelow as a medical membrane) 33. After each of these components
has been affixed together preferably by welding, each of these layers will be compressed
together to form the infection control product of the present invention.
Components of the infection control pillow product in the most preferred embodiment
[0060]
- Main Pillow Cover 31 manufactured of polyurethane (PU) coated polyamide - (preferably,
Redwood 'ICE' Fabric)
- Medical membrane 33 such as medical membrane MMT-302 produced by W.L. Gore & Associates,
Inc., 401 Airport Road, Elkton, Maryland, United States of America.
- Spun-bonded Polypropylene membrane 35.
- PU gasket 36.
Details of each component
Pillow cover 31
[0061] The pillow cover 31 is manufactured of 135 g/m
2 polyurethane (PU) Coated Polyamide.
[0062] The PU coating provides protection against fungi and bacteria.
[0063] The infection control product including the vent is washable at 75°C. The infection
control product is gentle to the skin and also has the advantage that the inclusion
of the vent in the product does not create noise which is, of course, undesirable
in particular when the product is used in a hospital environment by a patient.
Filter Membrane (Medical Membrane)
[0064] The filter membrane 33 is a breathable membrane which allows air to be expelled from
within the pillow when compressed thereby preventing the unwanted effect of 'ballooning'
around the patients head/mouth.
[0065] The breathable medical membrane 33 also protects the structure (including the RF
welded seams) of the infection control product, ensuring the seams are not overstressed
when the pillow is compressed, basically preventing a rupture should the entire pillow
be compressed.
[0066] The medical membrane 33 has been tested vigorously as a microbial barrier and performed
extremely well.
Spun-bonded polypropylene layer 35
[0067] The periphery shape and dimensions equal to medical membrane 33.
[0068] The purpose of including the spun-bonded polypropylene is to add greater strength
to the vent area. The spun-bonded polypropylene layer 35 is inserted behind the medical
membrane 33 and it prevents simple punctures from hands/fingers.
Polyurethane (PU) Gasket 36
[0069] The polyurethane gasket is slightly smaller than the rectangular RF weld area, yet
slightly larger than the medical membrane and spun-bonded polypropylene. This ensures
that the edge of medical membrane and spun-bonded polypropylene are completely sealed
down to the pillow cover surface. Thus the edges of each of the layers are sealed
and compressed, thereby resulting in a completely smooth, patient friendly, surface.
[0070] The purpose of the PU gasket 36 is to add more plastic to the weld area, allowing
more plastic to flow into the Spun-bonded polypropylene layer, the medical membrane
33 and the PU coated pillow cover, increasing the quality/strength of the bond of
the various layers.
Welds
1. Long welds along the pillow cover edges
[0071] The long welds along the edges of the pillow cover are fully RF welded. This gives
a seam which is completely impermeable to liquid.
2. Closing Weld to complete filled pillow
[0072] Whether RF welded or heat sealed closed, the closing weld encapsulates the pillow
filler and completes the impermeable peripheral seam.
Fire Testing
[0073] A complete pillow produced in accordance with the process of the invention, filled
and sealed, has undergone fire testing. The complete pillow performed extremely well
in the fire tests, scoring an FR rating of Crib 5.
[0074] Referring now to Figure 8, the components of the vent 32 are shown stacked on top
of the welding tool. The welding tool has a larger surface than the components, so
as to ensure that the edge around the perimeter of the vent 32 and the aperture 38
is completely sealed.
[0075] Referring now to Figure 9, a finished weld is shown, a glossy bead of PU is provided
around the perimeter of the membrane 33 and spun-bonded polypropylene 35. The PU ensures
the edge is sealed and impermeable.
[0076] The method of manufacture of the hermetically sealed infection bedding product such
as a cushion, pillow, duvet, mattress or such like, in accordance with the invention
comprises the steps of:
- a) providing a filter membrane,
- b) providing a strengthening layer,
- c) providing a gasket,
- d) providing a cover of the bedding product, the cover having an aperture;
- e) locating the PU gasket, the strengthening layer and the filter membrane in the
aperture,
- f) affixing the layers a), b), c) and the cover of the product together so that the
layers are sealed together and are impermeable to liquid, whereby the filter membrane,
strengthening material and the gasket are bonded together with the cover of the infection
control bedding product, at the aperture in the cover so as to provide a vent in the
infection control bedding product.
[0077] The layers of the filter medium 32 are bonded together by glueing or welding such
as heat welding, ultrasonic welding, compression welding or RF welding. Preferably,
the bonding is carried out by RF welding with the RF welding apparatus operating in
a range of 27.12 MHz ± 160 Kilohertz.
[0078] In order to produce the infection control pillow 30, a welding apparatus is used
in which the welding action required is performed effectively. The method for producing
the infection control product 30 as described above ensures that the product 30 can
be replicated and mass produced.
[0079] Thus, the present invention provides a pillow or the like which is particularly advantageous
for use in hospitals and other medical institutions as a safeguard against the spread
of bacteria and Hospital Acquired Infection (HAI), in general. The present invention
can also be applied to other bedding products such as mattresses, cushions including
wheelchair cushions and duvets, for example, which similarly have a sealed cover containing
resiliently deformable filling material.
[0080] It will be appreciated that though the invention has been described with reference
to a hermetically sealed pillow, the invention provides for infection control for
bedding and soft furnishings generally. Indeed, advantageously, the invention can
be applied in any situation where there is a regular change-over in persons using
pillows, duvets and the like to prevent cross-infection. In addition to high risk
areas such as hospitals and medical institutions generally, the invention can be applied
more widely in other situations where there is a regular turnover of persons using
this type of bedding and furnishings, such as in hotels, guesthouses and the like.
The infection control pillow and bedding products of the invention may also be used
in domestic applications to avoid problems with dust mites and fungal infections.
It is also envisaged that this type of pillow product could be incorporated in headrests
for airline seating, as well as having military applications including sleeping bags
and the like.
[0081] It is to be understood that the invention is not limited to the specific details
described here which are given by way of example only and that various modification
and alterations are possible without departing from the scope of the invention as
defined in the appended claims.
1. A hermetically sealed infection control bedding product such as a pillow, duvet, mattress,
cushion or such like having a sealed cover and having a resiliently deformable filling
material, comprising a vent means in the cover, characterised in that the vent means comprises a filter medium including a filter membrane for the removal
of particles of microbial size and wherein the filter medium also comprises a strengthening
layer of material for providing mechanical strength to the filter medium whereby the
filter medium allows air flow therethrough but is substantially impermeable to liquid
while maintaining a barrier to particles of microbial size.
2. A hermetically sealed infection control bedding product as claimed in claim 1 wherein
the layer of strengthening material included in the filter medium, comprises a material
providing mechanical strength, and preferably comprises a thermoplastic material.
3. A hermetically sealed infection control bedding product as claimed in claim 1 or claim
2 wherein the vent further includes a gasket adapted to ensure that edges of the vent
joined to the cover of the infection control product are sealed and impermeable to
liquid.
4. A hermetically sealed infection control bedding product as claimed in claim 3 wherein
the gasket is of dimensions corresponding to the dimensions of the aperture in the
cover of the infection control product into which the vent is located.
5. A hermetically sealed infection control bedding product as claimed in claim 3 or claim
4 wherein the gasket is manufactured of the same material as the cover of the infection
control product.
6. A hermetically sealed infection control bedding product as claimed in claim 1 wherein
the filter membrane includes means for substantially preventing liquid ingress, while
allowing air to permeate, said means being provided by the filter membrane comprising
a hydrophobic material or oleophobic material.
7. A hermetically sealed infection control bedding product as claimed in claim 6 wherein
the filter membrane is manufactured of an oleophobic expanded PTFE membrane including
a non-woven polyvinyl chloride (PVC) backing support.
8. A hermetically sealed infection control bedding product as claimed in any one of the
preceding claims wherein the filter membrane comprises a bacteriological filter so
as to prevent the ingress of bacteria to an interior of the cover.
9. A hermetically sealed infection control bedding product as claimed in claim 8 wherein
the filter membrane is adapted to block passage of particles having a size of 0.5
microns or greater; optionally wherein the filter membrane is adapted by having a
pore size of between 0.2 and 4 microns.
10. A hermetically sealed infection control bedding product as claimed in any one of the
preceding claims wherein the cover of the infection control bedding product such as
a pillow is manufactured of polyurethane coated polymeric material, for example polyurethane
coated nylon.
11. A hermetically sealed infection control bedding product as claimed in any preceding
claim wherein an aperture is formed in the cover of the product and is adapted to
receive the vent.
12. A hermetically sealed infection control bedding product as claimed in claim 11 wherein
the aperture in the cover of the infection control product is located so that the
seam of the filter medium and aperture is not integral with any perimeter seam of
the cover of the infection control product.
13. A method of manufacture of the hermetically sealed infection bedding product such
as a cushion, pillow, duvet, mattress or such like, comprising the steps of:
a) providing a filter membrane
b) providing a strengthening layer
c) providing a cover of the bedding product, the cover having an aperture adapted
to receive the filter membrane and strengthening layer; and
d) affixing the layers a), b) and the cover c) together so that the layers are sealed
together and are impermeable to liquid, whereby
the filter membrane and strengthening material are bonded together with the cover
of the infection control bedding product, at an aperture in the cover so as to provide
a vent in the infection control bedding product.
14. A method of manufacture as claimed in claim 13 wherein a gasket manufactured of thermoplastic
material is provided between steps b) and c) and the gasket is also bonded together
with the filter membrane and the strengthening layer, to the cover of the product;
optionally wherein the gasket is manufactured of the same material as the cover of
the product.
15. A method of manufacture as claimed in claims 13 to 14 wherein the layers are affixed
together by bonding; optionally wherein the bonding is carried out by glueing or welding.
1. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle, beispielsweise
ein Kissen, ein Duvet, eine Matratze, ein Polster oder dergleichen, mit einem abgedichteten
Bezug und einem flexiblen verformbaren Füllmaterial, das ein Entlüftungsmittel in
dem Bezug umfasst, dadurch gekennzeichnet, dass das Entlüftungsmittel ein Filtermedium umfasst, das eine Filtermembran zum Entfernen
von Partikel mikrobieller Größe enthält, und wobei das Filtermedium auch eine Festigungsmaterialschicht
umfasst, um dem Filtermedium mechanische Festigkeit zu verleihen, wobei das Filtermedium
ermöglicht, dass Luft durch dieses strömt, es aber im Wesentlichen flüssigkeitsundurchlässig
ist und gleichzeitig eine Barriere für Partikel mikrobieller Größe darstellt.
2. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 1,
wobei die Festigungsmaterialschicht im Filtermedium ein Material, das mechanische
Festigkeit bereitstellt, und vorzugsweise ein thermoplastisches Material umfasst.
3. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 1
oder 2, wobei die Entlüftung ferner eine Dichtung enthält, die eingerichtet ist, um
sicherzustellen, dass mit dem Bezug des Produkts zur Infektionskontrolle verbundene
Ränder der Entlüftung abgedichtet und flüssigkeitsundurchlässig sind.
4. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 3,
wobei die Dichtung Abmessungen aufweist, die den Abmessungen der Öffnung in dem Bezug
des Produkts zur Infektionskontrolle entsprechen, in die die Entlüftung angeordnet
wird.
5. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 3
oder 4, wobei die Dichtung aus dem gleichen Material wie der Bezug des Produkts zur
Infektionskontrolle hergestellt ist.
6. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 1,
wobei die Filtermembran ein Mittel umfasst, um das Eindringen von Flüssigkeit im Wesentlichen
zu verhindern und gleichzeitig ein Durchdringen von Luft zu ermöglichen, wobei das
Mittel von der Filtermembran bereitgestellt wird und ein hydrophobes oder oleophobes
Material umfasst.
7. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 6,
wobei die Filtermembran aus einer oleophoben ePTFE-Membran hergestellt ist, die einen
Vlies-Polyvinylchlorid-(PVC-)Stützträger enthält.
8. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach einem der vorstehenden
Ansprüche, wobei die Filtermembran einen bakteriologischen Filter umfasst, um das
Eindringen von Bakterien in ein Inneres des Bezugs zu verhindern.
9. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 8,
wobei die Filtermembran eingerichtet ist, um das Passieren von Partikeln mit einer
Größe von 0,5 µm oder mehr zu blockieren; optional wobei die Filtermembran eingerichtet
ist, um eine Porengröße zwischen 0,2 µm und 4 µm aufzuweisen.
10. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach einem der vorstehenden
Ansprüche, wobei der Bezug des Bettwarenprodukts zur Infektionskontrolle, beispielsweise
eines Kissens, aus polyurethanbeschichtetem Polymermaterial, z. B. polyurethanbeschichtetem
Nylon, hergestellt ist.
11. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach einem vorstehenden
Anspruch, wobei eine Öffnung in dem Bezug des Produkts gebildet ist, die eingerichtet
ist, um die Entlüftung aufzunehmen.
12. Hermetisch abgedichtetes Bettwarenprodukt zur Infektionskontrolle nach Anspruch 11,
wobei die Öffnung in dem Bezug des Produkts zur Infektionskontrolle derart angeordnet
ist, dass die Naht des Filtermedium und der Öffnung nicht integral mit einer Umfangsnaht
des Bezugs des Produkts zur Infektionskontrolle ist.
13. Verfahren zum Herstellen des hermetisch abgedichteten Bettwarenprodukts zur Infektionskontrolle,
beispielsweise ein Polster, ein Kissen, ein Duvet, eine Matratze oder dergleichen,
das die folgenden Schritte umfasst:
a) Bereitstellen einer Filtermembran
b) Bereitstellen einer Festigungsschicht
c) Bereitstellen eines Bezugs des Bettwarenprodukts, wobei der Bezug eine Öffnung
aufweist, die eingerichtet ist, um die Filtermembran und die Festigungsschicht aufzunehmen;
und
d) Befestigen der Schichten a), b) und c) miteinander, so dass die Schichten miteinander
versiegelt und wasserundurchlässig sind, wobei
die Filtermembran und das Festigungsmaterial am Bezug des Bettwarenprodukts zur Infektionskontrolle
an einer Öffnung in dem Bezug angehaftet sind, um eine Entlüftung im Bettwarenprodukt
zur Infektionskontrolle bereitzustellen.
14. Verfahren nach Anspruch 13, wobei eine aus thermoplastischem Material hergestellte
Dichtung zwischen den Schritten b) und c) bereitgestellt wird, und wobei die Dichtung
ebenfalls mit der Filtermembran und der Festigungsschicht an dem Bezug des Produkts
haften; optional wobei die Dichtung aus dem gleichen Material wie der Bezug des Produkts
hergestellt ist.
15. Verfahren nach Anspruch 13 bis 14, wobei die Schichten durch Haftung aneinander befestigt
sind, optional wobei das Haften durch Kleben oder Schweißen erfolgt.
1. Produit de literie de contrôle d'infection fermé hermétiquement tel qu'un oreiller,
une couette, un matelas, un coussin ou similaire comportant un élément de recouvrement
scellé et comportant un matériau de remplissage déformable élastiquement, comprenant
des moyens formant évent dans l'élément de recouvrement, caractérisé en ce que les moyens formant évent comprennent un milieu filtrant comprenant une membrane filtrante
pour le retrait de particules de taille microbienne, et dans lequel le milieu filtrant
comprend également une couche de matériau de renforcement pour fournir une résistance
mécanique au milieu filtrant, moyennant quoi le milieu filtrant permet une circulation
d'air à travers celui-ci, mais est sensiblement imperméable aux liquides tout en maintenant
une barrière aux particules de taille microbienne.
2. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
1, dans lequel la couche de matériau de renforcement incluse dans le milieu filtrant
comprend un matériau fournissant une résistance mécanique, et comprend de préférence
un matériau thermoplastique.
3. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
1 ou la revendication 2, dans lequel l'évent comprend en outre un joint conçu pour
garantir que les bords de l'évent joints à l'élément de recouvrement du produit de
contrôle d'infection sont scellés et imperméables aux liquides.
4. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
3, dans lequel les dimensions du joint correspondent aux dimensions de l'ouverture
dans l'élément de recouvrement du produit de contrôle d'infection dans lequel l'évent
est situé.
5. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
3 ou la revendication 4, dans lequel le joint est réalisé en le même matériau que
l'élément de recouvrement du produit de contrôle d'infection.
6. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
1, dans lequel la membrane filtrante comprend des moyens pour empêcher sensiblement
l'entrée de liquide, tout en permettant à l'air de pénétrer, lesdits moyens étant
réalisés par la membrane filtrante comprenant un matériau hydrophobe ou un matériau
oléophobe.
7. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
6, dans lequel la membrane filtrante est réalisée par une membrane en PTFE expansé
oléophobe comprenant un support en polychlorure de vinyle (PVC) non tissé.
8. Produit de literie de contrôle d'infection fermé hermétiquement selon l'une quelconque
des revendications précédentes, dans lequel la membrane filtrante comprend un filtre
bactériologique de manière à empêcher l'entrée de bactéries à l'intérieur de l'élément
de recouvrement.
9. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
8, dans lequel la membrane filtrante est conçue pour bloquer le passage de particules
ayant une taille de 0,5 microns ou plus ; optionnellement, dans lequel la membrane
filtrante est conçue en ayant une taille de pore comprise entre 0,2 et 4 microns.
10. Produit de literie de contrôle d'infection fermé hermétiquement selon l'une quelconque
des revendications précédentes, dans lequel l'élément de recouvrement du produit de
literie de contrôle d'infection tel qu'un oreiller est réalisé en un matériau polymérique
revêtu de polyuréthane, par exemple du nylon revêtu de polyuréthane.
11. Produit de literie de contrôle d'infection fermé hermétiquement selon l'une quelconque
des revendications précédentes, dans lequel une ouverture est formée dans l'élément
de recouvrement du produit et est conçue pour recevoir l'évent.
12. Produit de literie de contrôle d'infection fermé hermétiquement selon la revendication
11, dans lequel l'ouverture dans l'élément de recouvrement du produit de contrôle
d'infection est située de sorte que la jonction du milieu filtrant et de l'ouverture
ne soit pas d'un seul tenant avec une jonction périmétrique de l'élément de recouvrement
du produit de contrôle d'infection.
13. Procédé de fabrication du produit de literie de contrôle d'infection fermé hermétiquement
tel qu'un coussin, un oreiller, une couette, un matelas ou similaire, comprenant les
étapes :
a) de fourniture d'une membrane filtrante ;
b) de fourniture d'une couche de renforcement ;
c) de fourniture d'un élément de recouvrement du produit de literie, l'élément de
recouvrement comportant une ouverture conçue pour recevoir la membrane filtrante et
la couche de renforcement ; et
d) de fixation des couches a), b) et de l'élément de recouvrement c) les uns aux autres
de sorte que les couches soient scellées les unes avec les autres et soient imperméables
aux liquides, moyennant quoi
la membrane filtrante et le matériau de renforcement sont liés à l'élément de recouvrement
du produit de literie de contrôle d'infection, au niveau d'une ouverture dans l'élément
de recouvrement de manière à réaliser un évent dans le produit de literie de contrôle
d'infection.
14. Procédé de fabrication selon la revendication 13, dans lequel un joint réalisé en
un matériau thermoplastique est prévu entre les étapes b) et c) et le joint est également
lié avec la membrane filtrante et la couche de renforcement à l'élément de recouvrement
du produit ; optionnellement, dans lequel le joint est réalisé en le même matériau
que l'élément de recouvrement du produit.
15. Procédé de fabrication selon la revendication 13 ou 14, dans lequel les couches sont
fixées les unes aux autres par liaison ; optionnellement, dans lequel la liaison est
effectuée par collage ou par soudage.